HOMEVULNERABILITIESCVE-2021-3942
CRITICAL

CVE-2021-3942

CWE-119Published: December 12, 2022· Updated: Jun 17, 2026

9.8
CVSS v3.1

Official Description

Certain HP Print products and Digital Sending products may be vulnerable to potential remote code execution and buffer overflow with use of Link-Local Multicast Name Resolution or LLMNR.

NVD Source

Technical Analysis

CVE-2021-3942 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.

A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 9.8.

From a weakness classification perspective (CWE-119): Buffer overflow vulnerabilities can lead to arbitrary code execution or denial of service by corrupting adjacent memory.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.None
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected Vendors & Products

HP5400 product(s)
color laserjet cm4540 mfp cc419a firmwarecolor laserjet cm4540 mfp cc419acolor laserjet cm4540 mfp cc420a firmwarecolor laserjet cm4540 mfp cc420acolor laserjet cm4540 mfp cc421a firmwarecolor laserjet cm4540 mfp cc421acolor laserjet cm5525 mfp ce707a firmwarecolor laserjet cm5525 mfp ce707acolor laserjet cm5525 mfp ce708a firmwarecolor laserjet cm5525 mfp ce708acolor laserjet cm5525 mfp ce709a firmwarecolor laserjet cm5525 mfp ce709a+5388
Source: NVD CPE · 5423 total CPE entries

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
External links open in a new tab. Always verify in a controlled environment before use.

Official Patches & Advisories

All References (2)

Quick Facts

CVE IDCVE-2021-3942
CVSS Score9.8 / 10
SeverityCRITICAL
WeaknessCWE-119
CISA KEVNo
Affected1 vendor(s)
PublishedDec 12, 2022

Related CVEs (CWE-119)

Recommended Actions

  • Apply vendor patches immediately
  • Monitor CVE-2021-3942 in threat intel feeds
  • Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWatch. CVE data is provided under the NVD usage policy.